During an interview, Ernest Borgnine related that when he was initially approached by his agent with an offer to star in the pilot for the show, he turned it down (it was actually to be a drama, called "Seven Against the Sea", which was retooled into a comedy when the series was picked up by ABC.) Not long thereafter a boy showed up on Borgnine's doorstep selling candy. He told Borgnine that he looked familiar, but that he couldn't place him. Borgnine, who had already won an Oscar for his role in Marty (1955), asked the boy if he knew who played the lead character Paladin in the television series Have Gun - Will Travel (1957). The boy said, "Richard Boone." He likewise was immediately able to remember the names of several other television series stars, even though he couldn't remember who Borgnine was. After the boy left, Borgnine called his agent to ask if that Navy pilot was still available. When told that it was, Borgnine told him to accept--and so became a part of what eventually would be his signature television series.
Ens. Charles Parker (Tim Conway) often mentioned that he was from Chagrin Falls, OH. Conway grew up in Chagrin Falls in real life.
Ernest Borgnine served in the U.S. Navy during World War II as a Gunner's Mate on the anti-submarine vessel U.S.S. Slyph off the Atlantic coast. He served a total of ten years in the U.S. Navy, from 1935 through the end of the war. In 2004, he was made an Honorary Chief Petty Officer by the U.S. Navy in recognition of his support of the U.S. Navy throughout his career.
The crew's duties were: George "Christy" Christopher (Gary Vinson) - Quartermaster; Harrison "Tinker" Bell (Billy Sands) - Motor Machinist's Mate; Lester Gruber (Carl Ballantine) and Joseph "Happy" Haynes (Gavin MacLeod) -Torpedoman's Mate; Willy Moss (John Wright) - Radioman; Virgil Edwards (Edson Stroll) - Gunner's Mate
During the first season, Ernest Borgnine was the only one of the cast who appeared in the opening credits. From the second season on, Tim Conway and Joe Flynn also appeared.